The present invention relates to a device with components concentrically disposed and rotational in relation to each other wherein a rotational insert disposed in an external component having at east one seal with a sealed area acting upon an inner component is provided between said components.
A sealed area not being lubricated by its surrounding media is a principal problem in numerous sealing devices. This problem influences the life of the seals and requires the sealed areas to be relubricated within the limits of given maintenance intervals. Frequently the seals are embodied such that a small hollow space is available between two sealing lips in which a small amount of grease and, thus a very limited stock of lubricant only can be provided. Primarily, the insufficient lubrication is a particular problem for rotary shift seals because the life span of the seals suffers and/or an expensive relubrication is required in special maintenance intervals. Rotary shaft seals are used, for example, for sealing the hub in the rotational insert provided at the wheel support in tire inflating arrangements provided for the adjustment of the air pressure in tires. Here, the air being under atmospheric pressure is sealed by means of a rotary shaft seal from the air pressured by the tire and, thus, having a higher pressure.
The object of the invention is to provide a solution for the problem mentioned.
The given object of the invention is to provide a lubricant reservoir connected with the sealed area via bores, channels, or the like in the region of at least one inner component.
By means of the present invention it is ensured that continuous lubrication, continuous feeding of lubricant to the sealing lips or sealed areas can occur by means of a lubricant reservoir which is connected to the respective lubrication area or areas. On the one hand, said feeding is ensured by the working temperature being higher during operation in relation to the ambient temperature, causing the lubricant to liquify, and by the centrifugal forces occurring during operation.
In a particularly easy manner, this lubricant reservoir can be provided in a hollow space formed by two inner components.
In a particularly easy manner, this lubricant reservoir can be provided in a hollow space formed by two inner components.
In a preferred embodiment according to the invention, the lubricant is continuously squeezed from the lubricant reservoir to the sealed areas in order to ensure the permanent supply of lubricant to the sealed areas of the seals.
This can be done by a piston acting upon the lubricant in the lubricant reservoir.
In a particularly simple variant, a piston activation is provided such that said piston is acted upon by a pressure spring; alternatively or additionally the piston can be actuated with compressed air, in particular, in a computer controlled manner. The latter measure allows an additional supply of lubricant to the sealed areas at certain intervals.
The utilization of the device according to the invention is particularly advantageous for a rotational insert containing rotary shaft seals which seal gases from one another, particularly air, pressurized with different pressure. It is particularly important for seals of this type to sufficiently lubricate the sealed areas in order to avoid a time-consuming relubrication and time-consuming maintenance works.
Therefore, the device according to the invention can be used in a particularly advantageous manner as a component of a tire inflating arrangement wherein the wheel support is the exterior component and the hub and the drive shaft are the inner components.
Therefore, the present invention relates to a tire inflating arrangement having such a device as well.